A molecule critical to stem cell function plays a major role in determining human hair color, according to a new study. The study describes for the first time the molecular basis for one of our most noticeable traits. It also outlines how tiny DNA changes can reverberate through our genome in ways that may affect evolution, migration and even human history.

Astrophysicists have established that cosmic turbulence could have amplified magnetic fields to the strengths observed in interstellar space. "Magnetic fields are ubiquitous in the universe," said one of the researchers. "We're pretty sure that the fields didn't exist at the beginning, at the Big Bang. So there's this fundamental question: how did magnetic fields arise?"

Researchers have erased and reactivated memories in rats, profoundly altering the animals' reaction to past events. The study is the first to show the ability to selectively remove a memory and predictably reactivate it by stimulating nerves in the brain at frequencies that are known to weaken and strengthen the connections between nerve cells, called synapses.

Some cases of autism spectrum disorder (ASD) can result from environmental influences rather than gene mutations, research has shown. The findings shed light on why older mothers are at increased risk for having children with ASD, and could pave the way for more research into the role of environment on ASD.

Part of a woman's egg production involves a winnowing of the egg supply during fetal development. As much as 80 percent of a baby girl's egg supply is lost even before she is born. New research has gained new insights into the earliest stages of egg selection, which may have broad implications for women's health and fertility.

A new study of the colorful 'eyespots' on the wings of some butterfly species is helping to address fundamental questions about evolution that are conceptually similar to the quandary Aristotle wrestled with about 330 B.C. -- 'which came first, the chicken or the egg?' After a couple thousand years, we're getting closer to the right answer.

A new treatment for drug-resistant epilepsy with the potential to suppress seizures 'on demand' with a pill, similar to how you might take painkillers when you feel a headache coming on, has been developed by researchers. The treatment combines genetic and chemical approaches to suppress seizures without disrupting normal brain function. The technique was demonstrated in rodents but in future we could see people controlling seizures on-demand with a simple pill.